Colour in Aftershaves ???

Hi All,
I don't know if it has been asked before (I tried the search function), but is it necessary for colourants/dyes to be added to the aftershaves we all know and love, or is for mere appearance? (i.e. AV Blue, Musk, Skin Bracer etc...)
I thought of this when some AV Blue spilled on bathroom counter and I used my shave towel to soak it up, I noticed how much colour the towel soaked up.
Thoughts?
Thanks.

It is all for appearance.

Just for looks. Yellow number 5 and Blue number 1 aren't good for much else I don't think.

It looks cool.

Colour psychology is a very interesting subject, 'cos a significant factor in the way you experience anything is the mental filter in your ol' brain (I just read the post by the guy who found Proraso pre-shave to be literally nauseating&#8230. I'm pretty sure that if they had to conduct a formal study, most guys would report feeling a superior cooling sensation from blue-coloured Aqua Velva as opposed to the same product minus the colourant (or the same product tinted red, for example).